Why Your Cat Stopped Using the Litter Box

A cat that stops using its box is not being spiteful. Cats do not do revenge. There is always a reason, and it falls into one of three categories: medical, the box itself, or stress.

Medical first, always

Book a vet appointment before you change anything else. Urinary tract infections, bladder stones, cystitis, kidney disease, diabetes, arthritis and constipation all present as inappropriate toileting. A cat that associates the box with pain will avoid it even after the pain is treated.

A male cat straining and producing nothing is a life-threatening emergency. A blocked bladder kills within a day or two. Do not wait to see if it passes.

The box maths

The rule is one box per cat plus one. Two cats need three boxes. Most homes have one box for two cats and wonder why there is a problem.

• Size: at least one and a half times the length of the cat. Most commercial boxes are too small.
• Cover: many cats dislike hooded boxes because they trap smell and remove escape routes. Try uncovered.
• Litter: most cats prefer fine, unscented clumping litter. Scented litter is designed for humans, and cats often hate it. Depth of about 5cm.
• Cleanliness: scoop at least daily. A dirty box is the single most common cause.
• Liners annoy a lot of cats. So do strong-smelling disinfectants — wash with hot water and mild soap.

Placement

Quiet, accessible, with more than one escape route, away from food and water, and not next to a noisy washing machine or a load-shedding-triggered inverter that beeps. In a multi-storey house, one box per floor. Spread boxes out — three boxes in a row is one location as far as a cat is concerned.

Stress triggers

A new pet, a new baby, a house move, building work, a new cat visible through the window, or a change in routine. Cats also toilet outside the box when they feel ambushed by another cat in the home. Vertical space, hiding places, separate feeding stations and a synthetic pheromone diffuser all help.

Cleaning up

Enzymatic cleaner only. Anything else leaves a scent marker inviting a repeat performance. Never rub a cat's nose in it or punish — it increases stress, which is often the cause in the first place.